1. Field of the Invention
The present invention is related to a semiconductor apparatus, a manufacturing method of the semiconductor apparatus, and a camera module.
2. Description of the Related Art
A Wafer Level Chip Scale Package (WL-CSP) of an image sensor chip is proposed for downsizing and weight-saving of an image sensor package using a semiconductor integrated circuit and used for a camera module and the like. The WL-CSP is manufactured as follows. Specifically, a first conductive layer is formed on a main surface of a semiconductor chip (a semiconductor wafer). A through hole is formed in the wafer. A second conductive layer is formed in the through hole. A third conductive layer is formed on the back surface side of the wafer. A metal bump is arranged on the third conductive layer.
For example, WO 2005/022631 A1 discloses a semiconductor apparatus which can be used as an image sensor package. A through hole which pass through a semiconductor substrate (a semiconductor wafer) made by silicon in the direction of the thickness is formed. After that, an insulation film is formed on both of the inner wall surface of the through hole and the back surface of the semiconductor substrate (semiconductor wafer). A through conductive layer is formed in the through hole. And, via the conductive layer, front side conductive layer formed on the front side of the semiconductor substrate (semiconductor wafer) and an external terminal formed on the back side of the semiconductor substrate are electrically connected.
However, the semiconductor apparatus manufactured in such way has the possibility of low electric reliability. That is, a heat load during reflow mounting or temperature cycles causes a short circuit of the semiconductor apparatus by fractures of a back side insulation film or a front side insulation film, and a poor connection brought by increasing resistances by fracture of a front side conductive film.